Ford Focus ST Forum banner
1 - 20 of 24 Posts

·
Registered
Joined
·
1,678 Posts
Discussion Starter · #1 ·
I've done a search on here and can't find any info on how to remove/change it.

I looked at it on the car and it looks...well not easy!

Anybody willing to give some advice please?

Cheers
 

·
Super Moderator
2017 Audi S3 Sportsback
Joined
·
8,078 Posts
Are you looking to remove the upper plenum or the lower cast manifold section ??
 

·
Registered
Joined
·
611 Posts
I've done it, to check the green plenum seals as I had a possible leak.
Taking the plastic plenum out is not particularly taxing once the airbox is out of the way.

If you still have the standard airbox then it becomes a real pain of a job. To get the airbox out, you will need to drop the rad a couple of inches. You will also need to unbolt the ecu and loom to move it as It is attached to the airbox.

It sounds worse than it is, as you don't need to undo any water hoses.
You will need to get under the car to do this as the brackets are accessed from below.
A helping hand to get it back into position is helpful too.

If I can be of any further help, let me know.
Good luck
 

·
Registered
Joined
·
7,012 Posts
I didn't realise you just wanted to change the upper, I presumed you wanted the lower section out too.

The hardest part of the plenum is on the far left as you look down on it from the front of the car there's two bolts which are a nightmare to get to, you need a 1/4 inch drive socket set and ratchet and an extension bar, and prepare for cut knuckles.

Also there is a pipe going into the bottom of the plenum underneath, a small one, has a stupid hose clip on that ford use which is hard to get off, I snapped it with pliers and fitted a jubilee clip instead for ease.

The guide above is very good.

I've had my plenum off twice now, once to fit injectors and once to change the plenum completely.

I should add I don't have the standard airbox.
 

·
Super Moderator
2017 Audi S3 Sportsback
Joined
·
8,078 Posts
When you do the screws up that hold the plenum on Ian , do them up evenly and dont overtighten the ones to the furthest left and right ....the casting on the lower manifold is quite fragile


Not trying to scare you ...but this is what happens when you overtighten them !!!!
 

Attachments

·
Registered
Joined
·
1,104 Posts
I've done mine four times now, really really make sure you don't over tighten. I had to replace my lower inlet manifold after cracking it (details in my build thread)
 

·
Registered
Joined
·
1,678 Posts
Discussion Starter · #13 ·
Well it sounded ok till I read about the standard air box..that's what I have.
Have very little chance of getting under the car as no decent trolley jack.

Certainly don't like the thought of over tightening the bolts!!!!
 

·
Registered
Joined
·
7,012 Posts
Well it sounded ok till I read about the standard air box..that's what I have.
Have very little chance of getting under the car as no decent trolley jack.

Certainly don't like the thought of over tightening the bolts!!!!
I don't think over tightening is a big issue as long as you are careful, it doesn't need to be overly tight as long as its held in place. The Airbox is a pain.
 

·
Registered
Joined
·
732 Posts
I think you will be ok with the bolts as long as you start tightening the middle first, then the right hand side, then the left (weak side). The plenum is currently off my car waiting for the AS one to go on. It was a bit of a fiddle getting the bolts out as you have to do it by feel but not overly difficult!
 

·
Registered
Joined
·
1,678 Posts
Discussion Starter · #16 ·
I don't think over tightening is a big issue as long as you are careful, it doesn't need to be overly tight as long as its held in place. The Airbox is a pain.
But it needs to be air tight thou?

This forum is a world of knowledge.. muchly appreciated too, not sure if I want to change it now!
 

·
Registered
Joined
·
1,104 Posts
But it needs to be air tight thou?

This forum is a world of knowledge.. muchly appreciated too, not sure if I want to change it now!
The seal isn't made by the metal on metal of the contact of plenum and manifold. Each inlet has a rubber O ring which compresses and creates a seal. You only need to tighten it enough to compress this rubber.
 

·
Registered
Joined
·
4,604 Posts
Tighten down evenly starting from the middle, not in one go, do it in stages so it pulls down flat. I think peeps that broke them maybe tightened too much on one end before going at other bolts.
 

·
Captain Slow
Joined
·
16,275 Posts
Mine broke to


You'll know if it's broken as it well be a lumpy has hell on idle and cough and splutter!
 
1 - 20 of 24 Posts
Top